Sunday, September 18, 2011

Poa Section Madropoa is mostly restricted to high mountains of western
North America: the exception is one species, Poa cuspidata of the ne U.S.Of the 25 taxa total in the Section (FNA Vol.
24), most species are fairly widely distributed (except P. chambersii). P. porsildii, an alpine calciphile, is the sole
taxon, outside the limits of the western Cordillera (Rocky
Mountains-Cascade-Sierra axis).

Within the California Floristic Province, there are 8 endemic taxa of Poa
Section Madropoa, a distinctive concentration.

CAFP endemics

“Poa nervosa complex”

Poa rhizomata and Poa sierrae

Subsection Madropoa

Poa douglasii, Poa diaboli, Poa piperi and Poa atropurpurea

Subsection Epiles

Poa stebbinsii and Poa pringlei

Poa sierrae is odd in the clade: it is characterized by being rhizomatous,
dioecious and by the distinctive scaly ‘bulbils’ produced on the rhizomes.These ramets doubtless propagate by
fragmentation, so it is puzzling why P. sierrae is quite narrowly distributed.These ramets are nicely afforded 2x the page
space in FNA Vol. 24 (p. 550) –fame!

This season, I visited “Lewisia rock” in the Feather River canyon, and
collected P. sierrae at the type station.On August 1st, the plants were still green but had flowered
perhaps mid-June.Collecting the
material, I retained some rhizomes to cultivate.Now, 6 weeks later after being potted and
water, new growth is underway.

The top photo shows ramets field collected along a rhizome, in the
fully dormant state.

The middle photo shows the larger ramet of the top photo after being potted where the base was set just at the soil surface, and after 6 weeks has not yet left dormancy: about 2
cm long

The lower photo shows two ramets: the left one is about 2 cm long and nicely expanding.The smaller right-hand one is about 0.5 cm long and has just triggered.

Thursday, September 1, 2011

Today I de-potted a pot of Brodiaea matsonii.The 1-gal pot was the only pot of 4 pots which flowered in 2011; upon inspection, the mode of vegetative propagation was readily apparent.Daughter bulbs begin on the stem (putative in the sense that I refer to the portion of the corm just apical of the root pad).Being lax, I did not consult literature (Mecalf & Chalk would probably prove me anatomically wrong).The photo shows three large corms, each with a genet attached (Left to Right: 3 o’clock, noon, and 7 o’clock).

In monocots such as Brodiaea, vegetative propagation is perhaps numerically more important demograpically than sexual reproduction.